Also known as: Hematochezia / Melena
Blood in the stool can appear as bright red blood on toilet paper or in the bowl, or as dark, tarry stools.
Finding blood in your stool can be alarming, and it is a symptom that always warrants medical attention. Blood in the stool can look quite different depending on where in the digestive tract the bleeding is coming from. Bright red blood typically comes from the lower part of the digestive tract — the rectum or large intestine — and is often seen on toilet paper or coating the surface of the stool. Dark, tarry, or black stools (called melena) usually indicate bleeding higher up in the digestive tract, such as the stomach or small intestine.
The causes of blood in the stool range from relatively minor conditions — like hemorrhoids or a small anal tear — to more serious ones, including inflammatory bowel disease, diverticular disease, or colorectal cancer. Because the cause cannot be determined from appearance alone, any episode of visible blood in the stool should be reported to a healthcare provider, even if it seems to have resolved.
It is also worth knowing that certain foods and medications can change the color of stools in a way that mimics blood. For example, eating beets or black licorice can cause stools to appear red or dark. Iron supplements and bismuth-containing antacids can turn stools black. Your doctor can use a simple test to confirm whether actual blood is present.
There are several possible reasons you may be experiencing Blood in Stool. Here are the most common ones.
Hemorrhoids are swollen veins in the rectum or around the anus that can bleed when irritated during a bowel movement. They are one of the most common causes of bright red blood in the stool and are often associated with straining, constipation, or prolonged sitting.
An anal fissure is a small tear in the lining of the anus, usually caused by passing hard or large stools. It typically causes bright red blood on the toilet paper or stool surface, along with a sharp, stinging pain during and after bowel movements.
Diverticulosis is a condition in which small pouches (diverticula) form in the walls of the colon. These pouches can bleed — sometimes profusely — when a blood vessel near them ruptures, causing painless passage of large amounts of bright red or maroon blood in the stool.
Crohn's disease and ulcerative colitis are chronic inflammatory conditions that can cause ulcers, inflammation, and bleeding throughout the digestive tract. Blood in the stool is a common symptom, often accompanied by abdominal cramping, diarrhea, and unintentional weight loss.
Polyps are small growths on the inner lining of the colon or rectum that can bleed, sometimes only in small amounts detectable only by lab testing. Some polyps can become cancerous over time, making regular colorectal cancer screening an important preventive measure, especially after age 45.
Peptic ulcers are sores that develop on the lining of the stomach or the upper part of the small intestine. When they bleed, the blood is digested as it travels through the digestive tract, typically resulting in dark, tarry, foul-smelling stools rather than bright red blood.
Certain bacterial infections of the digestive tract — including those caused by Salmonella, Campylobacter, or Shigella — can cause inflammation and ulceration of the intestinal lining, leading to bloody diarrhea. These infections are often accompanied by fever, cramping, and nausea.
Angiodysplasia refers to abnormal, fragile blood vessels that can form in the lining of the colon or stomach. These malformed vessels can rupture and cause painless bleeding, and are a more common cause of gastrointestinal bleeding in older adults.
These approaches may help manage blood in stool at home. Always consult a healthcare provider if symptoms persist or worsen.
Eating more dietary fiber — from fruits, vegetables, whole grains, and legumes — can help soften stools and reduce straining during bowel movements, which may help prevent bleeding from hemorrhoids and anal fissures. Aim for 25 to 35 grams of fiber per day, and increase intake gradually to avoid gas and bloating.
Drinking plenty of water throughout the day helps keep stools soft and easier to pass, reducing the pressure on hemorrhoids and the risk of anal tears. Adequate hydration also supports overall digestive health and regular bowel movements.
Soaking the anal area in warm water for 10 to 15 minutes several times a day — especially after bowel movements — may help relieve discomfort from hemorrhoids or anal fissures and promote healing. A sitz bath basin that fits over a toilet seat is widely available at pharmacies.
Straining during bowel movements puts pressure on rectal veins and can worsen hemorrhoids or reopen anal fissures. Do not sit on the toilet for long periods, and consider using a small footstool to raise your feet slightly, which can help achieve a more natural squatting position.
When blood in the stool is reported, a doctor will typically begin with a physical exam, including a digital rectal examination to check for hemorrhoids, fissures, or masses. A fecal occult blood test can detect tiny amounts of blood not visible to the eye. Colonoscopy — a procedure using a flexible camera to view the entire colon — is the most thorough way to diagnose the cause of lower gastrointestinal bleeding. For suspected upper GI bleeding, an upper endoscopy may be performed. Blood tests to check for anemia and markers of inflammation may also be ordered.
See a doctor for any episode of blood in the stool, especially if it is recurrent, is accompanied by abdominal pain, weight loss, or changes in bowel habits.
Steps you can take to reduce the likelihood of experiencing blood in stool.
Eat a high-fiber diet rich in fruits, vegetables, and whole grains to maintain soft, regular stools and reduce straining.
Stay physically active, as regular exercise helps keep the digestive system moving and reduces the risk of constipation and diverticular disease.
Stay well hydrated by drinking at least 6 to 8 glasses of water per day to support healthy bowel function.
Get regular colorectal cancer screenings starting at age 45, or earlier if you have a family history of colorectal cancer or polyps.
Avoid overuse of non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen, which can irritate the stomach lining and increase the risk of peptic ulcers.
Not always — many cases are caused by relatively benign conditions like hemorrhoids or anal fissures. However, because blood in the stool can also signal more serious conditions such as colorectal cancer or IBD, it should always be evaluated by a healthcare provider, even if it seems minor or resolves quickly.
Bright red blood usually indicates bleeding from the lower digestive tract (rectum or colon), while dark red or maroon blood may suggest bleeding further up in the colon. Black, tarry stools typically indicate bleeding from the stomach or upper small intestine, as blood is partially digested during its passage. Very pale or clay-colored stools may suggest a problem with the liver or bile ducts.
Hemorrhoids typically cause small amounts of bright red blood — often just a few drops seen on toilet paper or the surface of the stool. Large amounts of blood or blood mixed throughout the stool are less typical of hemorrhoids and more likely to suggest another cause, such as diverticular bleeding or inflammatory bowel disease.
Eating large amounts of beets, red-colored drinks, red licorice, or tomato-based products can cause stools to appear reddish, which may look like blood. Black stools can be caused by iron supplements, bismuth subsalicylate (found in some antacids), or eating dark foods like black licorice. If you are unsure, a simple fecal occult blood test can confirm whether blood is actually present.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.